Most of the forgeries I have seen on this image is on the smaller (14" x 11" ?) 'giveaway' prints. While 99% of those are vertically signed, that does not disqualify authenticity on all items, especially the litho's.
Can someone correct my memory of the '88 show? My recollection was that there was a strict "no personalization / inscription" policy. Was that just for the individual tickets and not for the group package?